A magnetic resonance imaging test confirmed Monday that Ravens tight end Ed Dickson has a small hamstring tear, an injury that isn’t believed to be too serious but is magnified with Dennis Pitta already out for the season.

“There’s a little tear in there,” coach John Harbaugh said. “We’re going to hold him back for a week or so and we’ll see where we’re at. It’s going to be a matter of time, but it’s not going to be a long time.”

Harbaugh said that he expects Dickson, who caught 21 passes for 225 yards in 13 games last season, to be ready for the Ravens’ Sept. 5 opener against the Denver Broncos.

Dickson, however, will miss Thursday’s preseason opener against the Tampa Bay Buccaneers, leaving the Ravens with only fourth healthy tight ends. That group is headed by veteran Visanthe Shiancoe, who was signed last week after Pitta suffered the season-ending hip injury, and also includes Billy Bajema, Alex Silvestro and undrafted rookie free agent Matt Furstenburg (Maryland).

“We have enough tight ends to get us through Thursday for sure,” Harbaugh said. “We’ll be fine. We [may] have to address it then, depending on how we get out of that game.”

With Dickson being sidelined, Shiancoe (Morgan State) should get plenty of work with the first-team offense and get more of an opportunity to gain chemistry with quarterback Joe Flacco. The two have stayed after practiced with Shiancoe running some extra routes and Flacco throwing him the ball.

“Everything is about reps and repetitions, gaining confidence in yourself and the quarterback and the offense,” said Shiancoe who hasn’t caught a pass in a regular season game since the 2011 season. “I’m going to keep on building my building, brick-by-brick, keep working hard every day like I’m doing now. The coaches have plans [and they] are throwing me in there whenever they feel I’m ready, and that’s the plan.”

End zone

Running back Ray Rice left practice early; Harbaugh said he turned his ankle and it wasn’t serious. Safety Omar Brown also didn’t finish practice with an undisclosed injury, while James Ihedigbo returned after missing Sunday’s session with a neck injury. … With Jameel McClain (spine contusion) still sidelined and veteran Daryl Smith getting the day off, rookie Arthur Brown got some work with the first-team defense. … Asked what he’s most looking forward to about playing the Buccaneers on Thursday, rookie defensive tackle Brandon Williams said, “To hit someone else. That’s the biggest thing — to get out on the field and show people what the Ravens are all about.”

Every Monday during training camp, Baltimore Sun blogger and reporter Matt Vensel will take stock of the Ravens and identify three players (or position groups) on the rise and three who have struggled.